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<H1 ALIGN="CENTER">Module mod_auth</h1>

This module is contained in the <code>mod_auth.c</code> file, and
is compiled in by default. It provides for user authentication using
textual files.


<menu>
<li><A HREF="#authgroupfile">AuthGroupFile</A>
<li><A HREF="#authuserfile">AuthUserFile</A>
<li><A HREF="#authauthoritative">AuthAuthoritative</A>
</menu>
<hr>


<A name="authgroupfile"><h2>AuthGroupFile</h2></A>
<!--%plaintext &lt;?INDEX {\tt AuthGroupFile} directive&gt; -->
<strong>Syntax:</strong> AuthGroupFile <em>filename</em><br>
<Strong>Context:</strong> directory, .htaccess<br>
<Strong>Override:</strong> AuthConfig<br>
<strong>Status:</strong> Base<br>
<strong>Module:</strong> mod_auth<p>

The AuthGroupFile directive sets the name of a textual file containing the list
of user groups for user authentication. <em>Filename</em> is the absolute path
to the group file.<p>
Each line of the group file contains a groupname followed by a colon, followed
by the member usernames separated by spaces. Example:
<blockquote><code>mygroup: bob joe anne</code></blockquote>
Note that searching large groups files is <em>very</em> inefficient;
<A HREF="mod_auth_dbm.html#authdbmgroupfile">AuthDBMGroupFile</A> should
be used instead.<p>

Security: make sure that the AuthGroupFile is stored outside the
document tree of the web-server; do <em>not</em> put it in the directory that
it protects. Otherwise, clients will be able to download the AuthGroupFile.<p>

See also <A HREF="core.html#authname">AuthName</A>,
<A HREF="core.html#authtype">AuthType</A> and
<A HREF="#authuserfile">AuthUserFile</A>.<p><hr>

<A name="authuserfile"><h2>AuthUserFile</h2></A>
<!--%plaintext &lt;?INDEX {\tt AuthUserFile} directive&gt; -->
<strong>Syntax:</strong> AuthUserFile <em>filename</em><br>
<Strong>Context:</strong> directory, .htaccess<br>
<Strong>Override:</strong> AuthConfig<br>
<strong>Status:</strong> Base<br>
<strong>Module:</strong> mod_auth<p>

The AuthUserFile directive sets the name of a textual file containing
the list of users and passwords for user
authentication. <em>Filename</em> is the absolute path to the user
file.<p> Each line of the user file file contains a username followed
by a colon, followed by the crypt() encrypted password. The behavior
of multiple occurrences of the same user is undefined.<p> Note that
searching user groups files is inefficient; <A
HREF="mod_auth_dbm.html#authdbmuserfile">AuthDBMUserFile</A> should be
used instead.<p>

Security: make sure that the AuthUserFile is stored outside the
document tree of the web-server; do <em>not</em> put it in the directory that
it protects. Otherwise, clients will be able to download the AuthUserFile.<p>

See also <A HREF="core.html#authname">AuthName</A>,
<A HREF="core.html#authtype">AuthType</A> and
<A HREF="#authgroupfile">AuthGroupFile</A>.<p>
<hr>
<A name="authauthoritative"><h2>AuthAuthoritative</h2></A>
<!--%plaintext &lt;?INDEX {\tt AuthAuthoritative} directive&gt; -->
<strong>Syntax:</strong> AuthAuthoritative &lt; <strong> on</strong>(default) | off &gt; <br>
<Strong>Context:</strong> directory, .htaccess<br>
<Strong>Override:</strong> AuthConfig<br>
<strong>Status:</strong> Base<br>
<strong>Module:</strong> mod_auth<p>

Setting the AuthAuthoritative directive explicitly to <b>'off'</b>
allows for both authentication and authorization to be passed on to
lower level modules (as defined in the <code>Configuration</code> and
<code>modules.c</code> files) if there is <b>no userID</b> or
<b>rule</b> matching the supplied userID. If there is a userID and/or
rule specified; the usual password and access checks will be applied
and a failure will give an Authorization Required reply.

<p>

So if a userID appears in the database of more than one module; or if
a valid require directive applies to more than one module; then the
first module will verify the credentials; and no access is passed on;
regardless of the AuthAuthoritative setting.

<p>

A common use for this is in conjunction with one of the database
modules; such as <a
href="mod_auth_db.html"><code>mod_auth_db.c</code></a>, <a
href="mod_auth_dbm.html"><code>mod_auth_dbm.c</code></a>, <a
href="mod_auth_msql.html"><code>mod_auth_msql.c</code></a> and <a
href="mod_auth_anon.html"><code>mod_auth_anon.c</code></a>. These modules
supply the bulk of the user credential checking; but a few
(administrator) related accesses fall through to a lower level with a
well protected AuthUserFile.

<p>

<b>Default:</b> By default; control is not passed on; and an unknown
userID or rule will result in an Authorization Required reply. Not
setting it thus keeps the system secure; and forces an NSCA compliant
behaviour.

<p>

Security: Do consider the implications of allowing a user to allow
fall-through in his .htaccess file; and verify that this is really
what you want; Generally it is easier to just secure a single
.htpasswd file, than it is to secure a database such as mSQL. Make
sure that the AuthUserFile is stored outside the document tree of the
web-server; do <em>not</em> put it in the directory that it
protects. Otherwise, clients will be able to download the
AuthUserFile.

<p>
See also <A HREF="core.html#authname">AuthName</A>,
<A HREF="core.html#authtype">AuthType</A> and
<A HREF="#authgroupfile">AuthGroupFile</A>.<p>

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